Thank You for all the answers: This is the solution I have come up with.

while ($rows_le = $sth_le->fetchrow_hashref())
{
if ($rows_le->{'KPI'} eq 'PDP'&&$rows_le->{'SPECIFIC_PROBLEM'} eq 'PDP
+')
    {
            push @logged_events , $rows_le;
    }
}
[download]

I know this could be done in the SQL, however for my specific application I need to do the sorting at a later stage.